MONOGRAPH OF THE GENUS STROPIIIA. 
O o 
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Form of shell an oblong turret, with the first two whirls about 
equal in diameter, from the second, the shell slopes to an acute point, 
forming an angle of about forty degrees. The striations are few, thir- 
teen to the first whirl, very prominent, bulging, not greatly enlarged 
in the middle, regular and crooked, and not arranged in lines. They 
are not an equal distance apart, but the interspaces between them are 
always twice as wide as the prominences ; $nd there are longitudinal 
sub striations indicated in some of the depressions. Both striations 
and interspaces are crossed by narrow*, transverse lines, which are, 
however, everywhere about an equal distance apart, without any un- 
marked interruptions in the center of the whirls. These lines are 
about .01 apart, and there are about twenty of them on the first whirl 
beneath the frontal bar. The suture is deep. 
Aperture, not very small, about as high as wide and open. The 
lower tooth is not prominent, rising gradually from the floor of the 
mouth, is about twice as long as high ; it is about central in position, 
and is set back about once its length from the frontal bar. The upper 
tooth begins a little back of the lower, is about its size, and is placed 
low on th£ column. 
The margin is not produced quite as far forward as the diameter of 
the shell, is inclined backward on the upper left side, and the lower 
right further than on the corresponding portions cn the opposite side 9 
in this respect resembling S. scalarina, hence this peculiarity becomes 
sub-generic. It is considerably flanging, especially on the right side, 
about .07, and here it is somewhat roughened by minute tubercles 
which are arranged in radiating or transverse lines. The frontal bar 
is very prominent, extending well out beyond the shell. The trans- 
verse striations appear on the right side of the tooth, and continue far 
within the shell. 
Color of shell, pale yellowish, externally, but the specimens have 
evidently been cleaned and thus the transverse lines do not contain any 
soil. Within, very pale yellowish, becoming white on the margin. 
DIMENSIONS. 
Size of type, 1.12 by .40 ; size of one other specimen examined, 1.20 
by .40. 
OBSERVATIONS. 
Rather singularly after my article upon S. scalarina was in type, 
1 found two specimens of S. faxoni in the museum collection of which I 
